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R100 handlebar diameter twilight zone?

Went to install some sweet Fehling Euro bars on the 91 R100 today...22mm standard size for all airhead bars...right? well, they were too big in diameter...i do not have calipers, but with a ruler, my stock bars measure 20mm in diameter....my controls will not fit the 22s...have searched many threads, but no mention of 20mm bars...nor can I find any for sale anywhere...what gives...any ideas?

Thanks Kurt for your reply. both the Fehling site and Flanders site say that 22 millimeters is the BMW standard. But my bars are only 20 millimeters I can't find anyone selling 20 millimeter bars. is there more than 1 standard bar diameter? Really hoping to avoid grinding/sanding the replacement bars down...thanks

I'm unclear are what you're asking. You mention wanting to avoid sanding/grinding the bars to fit your control 22mm perches, but state that they are 20mm in diameter.

There is a slight difference in bar diameters based on the "schedule" of tubing that the manufacturer uses. Occasionally, as a result of the manufacturing process, the end of the tube can become slightly flared and not fit into the perch.

If the bars are too tight to fit into your perches, perhaps all that is needed is to carefully open up the "clamping" end with a large screwdriver, etc.

From what I discern from Max's BMW microfiche and a 91 R100 handle bar part number, it seems the part changed after 1990. A search using the part number of 32 72 1 451 734 (throttle handle housing) on Max's site yields that it fits 1990-96 airheads and K bikes. Euro bars for a K-bike may work OK. Good luck!

Edit: Ok, it seems the K-bike Bars are also 22 mm. So, I have no idea. Maybe the handlebar controls have a spacer to fit the smaller diameter bars?

I went and measured the bars on my 82 R100RT and 91 K100LT. They are both 22 mm.

2004 R1150RT 151,500 miles , 1991 K100LT 128,000 miles, 1982 R100RT 106,900 miles
Total 386,400 BMW miles
AMA,BMWRA,BMWMOA
The cheapest thing on a BMW is the nut that connects the handlebars to the seat.

Handlebars

Before you go lookong for more handlebars, get the true diameter measured. For some reason, some of those bars are just a tad wider at the ends. A little time on a bench grinder will take the fat spot off and the clutch and brake perches will slide on.
Just something I noticed with the Fehling bars.

Before you go lookong for more handlebars, get the true diameter measured. For some reason, some of those bars are just a tad wider at the ends. A little time on a bench grinder will take the fat spot off and the clutch and brake perches will slide on.
Just something I noticed with the Fehling bars.

Indeed, I had to do this to get the perches on:

Another issue is that the straight portion of the bar wasn't long enough for /6 controls. I could have lived with it and made it work if I hadn't planned to use bar end mirrors. I ended up with the Flanders "sidecar" bar--the position is nearly identical.

I'm wondering what a caliper measurement of the OP's bar would be--the end looks to be swaged down a wee bit to get that 20mm reading.

mystery solved...got some digital calipers and the Fehling bars that i have struggled with are actually 22.59 mm in diameter...also slightly out of round...just enough to cause me grief...my stock bars come in at 21.9 mm....I am working with seller to exchange...going to insist on measurement before shipping this time....